Masonry drill



May 27, 1952 M. J. STEFFES 2,598,459

MASONRY DRILL Filed Feb. 7, 1947 IN V EN TOR.

MZZa/I J? 556 76 5.

Patented May 27, 1952 iii-t UNITED STATES AT T o Fl-ca-l? MiltonJ.Stefies, Dearborn, "Mich., assignor to Super- Tool Company, Detroit,Mich, 'a'corpo ration of Michigan 7 g Application February 7, 19.47,Serial No. 727,027 I 1 Claim: (01. 255 61) 1 2 This invention relates toa masonry drill, and mama t t 'enk a Each of thejend' faces moreparticularly to such a drill adapted to be H and l9 iscut backrearwardlycof 'ajcutting either manually or machine operated. edge 2']at the. forward "edge thereof to 'pi ovide The p i p O j ts of thisinvention are to conventional relief for the cuttingedge.

pr a m nry rill h vi ,a poly n y The side edges 23 and 25'of'the'drill1bitji5 ped shank so that when the shank is supp r havetheir forward edges, adjacent each of the in an operating chuck to drillstone, brick or the cutting edges 21 dubbed off as t 29 in a like, sppage will not occur between the shank ventional manner, so as toprevent breaking and chuck; t Pr v a m s nry ool havin a thereof andeliminate rapid wearing which would p lye lly sh ped h nk nd a drill bitsecure 0 vary the diameter of the hole to be drilled. Rearin one end ofsaid shank so as to make h wardly of the dubbed portion 29 each of theside maximum use of the diameter of said shank and edges 23 and 25 iscut back as at 3| to provide thus provide the strongest possibleconnection conventional side clearance therefor between said drill bitand shank; to provide a The ends 30 of the flat sides 26 of the shankmasonry tool having a polygonal shank and a 9, adjacent the end faces ofthe drill bit l5, are drill bit secured in one end thereof, in which thecut parallel to the end faces of the drill bit and end of said Shankadjacent the drill bit is shaped relieved rearwardly at an angle similarto the in such a manner as to better reinforce said drill relief angleof the end faces. It will be noted that bit and still permit the mostefilcient cutting by the forward abutting edge of each flat side 26 ishe l er; d to provide a masonry tool whi spaced from its respective edgeof each of the is simple in construction, inexpensive to manu end faces,a distance equal to the width of the facture, and efiici n in Operationend faces, so as to abut both the cutting faces These and other objectsof this invention will and opposite faces of the drill bitbecomeapparent from the following detaile The opposite end of the shank 9,from the scription, taken in conjunction with the accoma m t [5, isadapted m b engaged i any p ny n dr wing in which; conventional chuck,for a hand motor, machine, ure 1 is a side elevational vlew of e or thelike, but in the embodiment illustrated in bodiment of this mv thedrawing is shown engaged in a three-jawed Fig. 2 is a plan view of aportion of the structure chuck 3g AS can be seen in Fig 1, t th jawsillustrated in Fig. 1; 33 engage three of the opposed fiat sides 26 ofthe 3 View partially in i and Wertiauy shank 9 so as to prevent, orgreatly reduce, any in elevation taken along the lin 33 of Fig. 2;slippage which may occur between the jaws 33 4 is an end elevation-a1View of the and the shank when the tool is in operation, such tureillustrated in Fig. l

Fig. 5 is a cross-sectional view taken along the emmwei line 55 of g- Inthe embodiment illustrated in Figs. 6 and 7, Fig. 6 1s a e e o l new ofa further the drill bit I5 is identical with the drill bit embodiment ofi 1nVe11t10n, and previously described and the shank 9 is of the Fig. 71s a view in end elevation of the structure same Shape However, in theembodiment m 1llustrated1nF1g.6. trated in Figs. 6 and 7 the endportions of the Referring now to the drawing, it will be seen Shank 9 ch d that the masonry drill of this invention includes in a i g lg fig i'ifig g gggfi a hexagon-shaped shank 9 having a, shallow slot II at oneend thereof which extends transversely 55:2 x 5122 22 2 g i t i of theacross said shank through diametrically opposed 4 27 of ea h f th Ce o 8cu edge aplces l3 thereof. A drill bit generally indicated t i o 8 enaces i that Is the at I5 is positioned within the slot n and rigidly Sdes Whmh abut the cuttmg face each secured to the shank 9 by anyconventional side of tool' are Shaped and located in a means, such asbrazing, as illustrated in Fig. 1. slmflar to the fiat side ends 30Previously The drill bit '5 is formed with a pair of described. However,the ends of the fiat sides 35, clined end faces 11 and I9 whichintersect at Whmh abut the Opposite e m the u ting the center of saidbit along a diagonal edge 2| face on each side of the drill bit, arepositioned which form t point of t m g The pso as to be flush with therear edge of each end posite ends of each of the end faces I! and I9 fce I! and I9 and are relieved at the same angle terminate at side edges23 and 25 extending 6!!v as the end faces so as to provide reinforcingexas often occurs when a cylindrical type shank is 3 tensions thereforso as to give greater support to said drill bit.

It will therefore be seen that a masonry tool is provided whicheliminates the common difficulty now prevalent wherein slippage occursbetween the operating chuck and the shank of the tool, and-whichprovided with a drill bitwhich will cut with the maximum of eii'iciencyand which is less liable to breaker cause breakage of the shank endadjacent to the drill bit. Likewise, the drill shank, while shown as ofa hexagonal shape, may be of any polygonal shape, the flat sidesproviding clearance for the discharge of loosened particles upwardlyalong the shank and out of the hole as it is being drilled. This is adecided advantage over a cylinder shank which rotates within thecollection of particles without disturbing and causing them to rise fromthe hole.

I claim:

Adrill including a hexagonal rod engageable by a driving tool at one endand having a slot in the opposite end extending through apices atdiametrically opposite sides of the rod, and a bit secured in said wallof a width substantially wider than the dimension across the apices ofsaid rod so as to extend therebeyond, the top and side edges of the bitbeing relieved in opposite directions on opposite sides of the centerthereof, the end of the bit sloping from the center to the sides withthe meeting line at the center disposed angularly, with the center ofthe line located on the center of thebit.

MILTON J. STEFF'ES.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS

